package com.sky.service.impl;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.sky.constant.MessageConstant;
import com.sky.dto.UserLoginDTO;
import com.sky.entity.User;
import com.sky.exception.LoginFailedException;
import com.sky.mapper.UserMapper;
import com.sky.properties.WeChatProperties;
import com.sky.service.UserService;
import com.sky.utils.HttpClientUtil;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Service;

import java.time.LocalDateTime;
import java.util.HashMap;

@Service
@Slf4j
@RequiredArgsConstructor
public class UserServiceImpl implements UserService {

    //wx服务接口地址
    public static final String WX_LOGIN = "https://api.weixin.qq.com/sns/jscode2session";
    public final WeChatProperties weChatProperties;

    public final UserMapper userMapper;

    /**
     * 微信登录
     *
     * @param userLoginDTO
     * @return
     */
    @Override
    public User wxLogin(UserLoginDTO userLoginDTO) {

        //1.将获取openid的方法抽离出去
        String openid = getOpenId(userLoginDTO.getCode());

        //2.判断openid是否为空，如果为空，则登录失败，抛出异常
        if (openid == null) {
            throw new LoginFailedException(MessageConstant.LOGIN_FAILED);
        }

        //3.openid不为空，则判断这个openid是否是我们的新用户
        User user = userMapper.getByOpenId(openid);
        if (user == null) {
            //4.如果是新用户，则自动完成注册，将用户保存到数据表中
            user = User.builder()
                       .openid(openid)
                       .createTime(LocalDateTime.now())
                       .build();
            userMapper.insert(user);
        }

        //5.返回用户对象
        return user;
    }

    /**
     * 调用微信接口服务，获取微信用户的openid的方法（抽离）
     *
     * @param code
     * @return
     */
    private String getOpenId(String code) {

        //1.调用wx接口服务，获得当前用户的openid
        HashMap<String, String> map = new HashMap<>();
        map.put("appid", weChatProperties.getAppid());
        map.put("secret", weChatProperties.getSecret());
        map.put("js_code", code);
        map.put("grant_type", "authorization_code");
        String json = HttpClientUtil.doGet(WX_LOGIN, map);

        JSONObject jsonObject = JSON.parseObject(json);
        String openid = jsonObject.getString("openid");

        return openid;
    }
}
